"Brain insulin may act as a satiety signal during the postprandial period and is associated with decreased appetite and reduced intake of highly palatable food, according to a study published online Feb. 16 in Diabetes.

Manfred Hallschmid, Ph.D., from the University of Lübeck in Germany, and colleagues investigated the role of brain insulin signaling in the control of food intake. In two groups of healthy women, 160 IU insulin or vehicle were administered after lunch, and two hours later, the consumption of cookies of varying palatability was evaluated under the pretext of a taste test. Intranasal insulin was administered to fasted females as a control study.

The researchers found that, compared with placebo, insulin administration in the postprandial state, but not in the fasted state, decreased appetite along with intake and rated palatability of the most palatable snack offered. Intranasal insulin administration was associated with a small decrease in plasma glucose, but no effect on serum insulin concentration was seen.

"Postprandially administered intranasal insulin enhances the satiating effect of meals and reduces palatable snack intake, suggesting that insulin acts as a relevant signal in the short-term regulation of satiety in humans," the authors write. "Considering that the rewarding effect of palatable food overriding the homeostatic control of energy intake may promote obesity, insulin's potential to curb the appetite for hedonically salient, calorie-rich food deserves particular attention."

This study suggests that building meals around low-energy density foods that significantly raise insulin levels, such as potatoes, rice, and the like, could curb appetite for highly palatable snacks.

It also suggests inversely that eating meals that minimize insulin release might result in less post-meal satiety and increased appetite for snacks.

Perhaps this provides partial explanation for the low prevalence of obesity in nations like Japan, where the cuisine revolves around a highly insulinogenic starch like white rice.

That study is interesting. People on the control meal clearly had the lowest postprandial insulin response. Yet all meals yielded similar postprandial glucose curves. What do we make of this?

I think this suggests that insulin sensitivity was highest in the control subjects (less insulin required to regulate glucose levels).

If this also correlates with brain insulin sensitivity (not sure if that leap is reasonable or not), then we'd expect less insulin to be required to trigger the same appetite-suppressing effect in the control group.

Yes, I think the study cited by Renaud only demonstrated that fats decrease insulin sensitivity. Most likely they decrease sensitivity in the brain equally to the peripheral tissues. This would probably mean that the lower fat group gets more satiation from less insulin.

Most Published Research Findings Are FALSE

In the August 2005 publication of the online PLOS, John Ioannidis thoroughly explained "Why Most Published Research Findings Are False." He showed that "Simulations show that for most study designs and settings, it is more likely for a research claim to be false than true. Moreover, for many current scientific fields, claimed research findings may often be simply accurate measures of the prevailing bias."

I don't remember when I first read his paper (probably no later than 2010), but I do know that I didn't begin to take him very seriously until about February 2017. Up until then, I thought that I could discover the truth about diet, nutrition and health by sorting through and analyzing published diet and nutrition research, which to say the least presents contradictory findings from different camps with different biases.

In late 2016, after more than 5 years eating an apparently nutrient-dense, high protein vegan diet, I had a blood test that showed that I had significantly low levels of globulin and phosphorus, indicating that I was likely not getting adequate protein or phosphorus from that diet.

Since then, I have worked on ridding myself of the belief that published diet and nutrition "science" or research is credible by virtue of its publication. I have worked on switching to relying on my own direct experience and senses of need, preference, taste, and satisfaction to guide my food choices. I am hoping to help others do the same.

If I could relay only one message from this point forward it would be: DON'T PUT YOUR FAITH IN SCIENCE AND DON'T RELY ON AUTHORITIES. BECOME SELF-RELIANT AND AUTONOMOUS.

Disclaimer

At one time I used this blog to explore and support the theory and practice of modernized, highly animal-based paleo and low-carb diets.

As I evolved, I became a paleo-diet heretic, and this blog became an exploration and presentation of the evidence values that support the practice of a whole foods plant-based diet.

Everything changes, and my experience, knowledge and understanding are no exception. In short, I have found the weaknesses and faults in plant-based ideology and practice as well.

I have tried to digest and assimilate the apparently conflicting information coming from the opposite ends of the diet debates (meat-based and high-fat vs. plant-based high-carbohydrate).

I have incorporated that new information into my world view and perspective and in the process revealed and corrected my errors when necessary.

The Chinese sage Chuang Tzu observed: "Tao is obscured when men understand only one pair of opposites, or concentrate only on a partial aspect of being. Then clear expression also becomes muddled by mere wordplay, affirming this one aspect and denying all the rest. The pivot of Tao passes through the center where all affirmations and denials converge. He who grasps the pivot is at the still-point from which all movements and oppositions can be seen in their right relationship... Abandoning all thought of imposing a limit or taking sides, he rests in direct intuition. "

Through understanding and experimenting with the dietary opposites, in late February 2017 I came to an understanding of the still-point between the extremes and the role of "intuition" from one's True Nature in solving the apparent dilemma.

About Me

I am a member of MENSA who has not always made smart choices. I have a master's degree in philosophy, and do my best to pursue truth and virtue. I have made mistakes in public, and have not been afraid to admit it. I believe that if I'm not making mistakes, I'm not learning or growing or living fully. Like Thoreau, I believe that "life is an experiment to a great extent untried," and that a philosopher should show by example a better way of life, not just spout doctrines and arguments. I value freedom and abhor slavery. I have a master's degree in Oriental medicine and the course work equivalent of a bachelor's degree in nutrition. I seek health, fitness, and longevity through self-discipline in physical training and food. In short, I practice macrobiotics: philosophy, freedom, fitness, and food. Hopefully others can learn from my successes and my mistakes.